Recent discoveries that high prolificacy in sheep carrying the Booroola gene (FecB) is the result of a mutation in the BMPIB receptor and high prolificacy in Inverdale sheep (FecX(I)) is the result of a mutation in the BMP15 oocyte-derived growth factor gene have allowed direct marker tests to be developed for FecB and FecX(I). These tests were carried out in seven strains of sheep (Javanese, Thoka, Woodlands, Olkuska, Lacaune, Belclare, and Cambridge) in which inheritance patterns have suggested the presence of major genes affecting prolificacy and in the prolific Garole sheep of India, which have been proposed as the ancestor of Australian Booroola Merinos. The FecB mutation was found in the Garole and Javanese sheep but not in Thoka, Woodlands, Olkuska, Lacaune, Belclare, and Cambridge sheep. None of the sheep tested had the FecX(I) mutation. These findings present strong evidence to support historical records that the Booroola gene was introduced into Australian flocks from Garole (Bengal) sheep in the late 18th century. It is unknown whether Javanese Thin-tailed sheep acquired the Booroola gene directly from Garole sheep from India or via Merinos from Australia. The DNA mutation test for FecB will enable breeding plans to be developed that allow the most effective use of this gene in Garole and Javanese Thin-tailed sheep and their crosses.

Three breeds of Javanese sheep are described briefly and data suggesting the segregation of a gene with large effect on ovulation rate and litter size are presented. The three breeds are Javanese Thin Tail (JTT), Javanese Fat Tail (JFT) and Semarang (SEM), the last possibly a substrain of JTT. All three breeds have mean mature ewe weights under 30 kg. Ovulation rate and litter size did not differ significantly among the three; all had litter sizes of up to 4 or 5 with a mean for mature ewes of approximately 2. Ovulation rate ranged from 1 to 5 and had an average within-breed repeatability of .8 within season and .65 between seasons. Within-breed repeatability of litter size was .35 +/- .06. Prenatal survival in pregnant ewes with two, three and four or more ovulations averaged 93, 88 and 86% over two seasons. Dams that had at least one ovulation rate or litter size record greater than or equal to 3 produced two groups of daughters in approximately equal numbers: one group with many records greater than or equal to 3 and mean ovulation rate and litter size of 2.73 and 2.31, respectively, and one group with ovulation rates and litter sizes of 1 or 2 and corresponding means of 1.39 and 1.38. Dams with ovulation rate or litter size records of only 1 or 2 produced daughters in which over 90% had records of only 1 or 2. Estimated heritabilities for the mean of approximately three ovulation rate or litter size records from these daughter-dam comparisons exceeded .7. These results suggest segregation of a Booroola-type gene, one copy of which increases ovulation rate by about 1.3 and litter size by .9 to 1.0. Relationships between duration of estrus and ovulation rate, and between timing of release of luteinizing hormone and number of eggs shed, resemble the pattern in Booroola Merino more closely than that in Finnish Landrace or Romanov, supporting the hypothesis of a major gene.

ABSTRAK Tujuan penelitian adalah untuk mengkarakterisasi ukuran-ukuran tubuh (morfometrik) dan jarak genetik antara enam populasi kambing lokal Indonesia. Analisis morfometrik dan kanonikal dilakukan untuk mengetahui hubungan kekerabatan dan ukuran tubuh yang dominan untuk menentukan pengelompokan pada kambing Benggala (n=96), Marica (n=60), Jawarandu (n=94), Kacang (n=217), Muara (n=30), dan Samosir (n=42). Analisis diskriminan digunakan untuk mengelompokkan parameter bobot badan dan ukuran-ukuran tubuh. Hasil penelitian menunjukkan bahwa bobot badan dan ukuran-ukuran tubuh (panjang badan, tinggi pundak, lebar dada, tinggi pundak, lingkar dada, tinggi dan lebar tengkorak, panjang dan lebar ekor, panjang dan lebar telinga) pada kambing Muara lebih tinggi (P<0,05) dibandingkan dengan populasi kambing lainnya, dan paling rendah pada kambing Marica. Jarak genetik paling dekat terdapat pada kambing Marica dan Samosir (11,207) dan paling jauh pada kambing Muara dan Benggala (255,110). Tingkat kesamaan paling tinggi antar individu dalam populasi dijumpai pada kambing Kacang (99,28%) dan paling rendah pada kambing Samosir (82,50%). Analisis kanonikal menunjukkan bahwa ukuran tubuh paling dominan sebagai pembeda antar enam populasi kambing lokal yang diamati antara lain: lingkar kanon, ukuran tubuh, lebar tengkorak, tinggi tengkorak, dan lebar ekor. Hasil analisis jarak mahalonobis pohon fenogram dan kanonikal menunjukkan bahwa enam populasi masing-masing berdiri sendiri, sehingga dibedakan menjadi enam rumpun, yaitu rumpun kambing Muara, Jawarandu, Kacang, Benggala, Samosir, dan Marica. Tingkat keragaman bobot badan dan panjang badan sangat tinggi, sehingga peluang peningkatan produksi dapat dilakukan melalui program persilangan dan seleksi.

Increasing milk yield per cow is considered a promising climate change mitigation strategy for small-scale dairy farms in developing countries. As it can be difficult to increase cow productivity, mitigation options beyond this production strategy need to be identified. The aim of this study was to identify entry points for mitigation of GHG emissions in small-scale dairy farms in Lembang Sub-district, West Java, Indonesia. Data on herd composition, productivity, feeding, and manure management were collected in a survey of 300 randomly selected dairy farms. Characteristics of farms with the 25% lowest (<3291 kg milk/cow/y), medium 50% (3291-4975 kg milk/cow/y), and 25% highest milk yields (≥4976 kg milk/cow/y) were compared. Life cycle assessment was then performed to estimate the cradle-to-farm gate GHG emission intensity (EI) of farms. The relationship between EI and milk yield per cow for all farms was modeled and farms with an EI below and above their predicted EI were compared ("low" and "high" EI farms). Results showed that milk yield explained 57% of the variance in EI among farms. Farms with medium and high milk yields were more often specialized farms, fed more tofu waste and compound feed, and had higher feed costs than farms with low milk yields (P < 0.05). Farms with high milk yields also applied less manure on farm land than farms with low milk yields (P < 0.05). Low EI farms had fewer cows, and fed less rice straw, more cassava waste, and more compound concentrate feed (particularly the type of concentrates consisting largely of by-products from milling industries) than high EI farms (P < 0.05). In addition, low EI farms discharged more manure, stored less solid manure, used less manure for anaerobic digestion followed by daily spreading, and applied less manure N on farmland than high EI farms (P < 0.05). Some associations were affected by confounding factors. Farm management factors associated with milk yield and the residual variation in EI were considered potential entry points for GHG mitigation. Feeding less rice straw and discharging manure, however, were considered unsuitable mitigation strategies because of expected trade-offs with other environmental issues or negative impacts on food-feed competition.

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